Just because they're kids doesn't mean you can't teach them birthday party etquette at a young age.

Story highlights

It's good to teach your child about opening gifts and receiving graciously.

For younger children, you could ask questions about what their friend might enjoy

Help your child learn to be the bigger person if they happen to find themselves not invited

Real Simple  — 

This article originally appeared on LearnVest.com.

Once your kids are old enough to spend time around other kids – whether it’s at classes, daycare or school – you can expect one thing to pop up like clockwork.

We’re talking about birthday party invitations … and they just keep coming and coming and coming.

You may think, Oh, kids’ parties are simple affairs. Balloons, cake, presents, done.

But there are actually plenty of money issues that arise regarding birthday parties, whether you’re hosting, or your kid is attending. Namely:

-How much should you spend on gifts?

-What’s the appropriate amount of money to spend on gift bags?

-What should you do if someone gives your kid an inappropriately expensive present?

Because these are tricky issues, we decided to go right to the source. Here, Lizzie Post, great-great-granddaughter of Emily Post and co-author of ” The 18th Edition of Emily Post’s Etiquette,” answers your most pressing questions about kids’ birthday party etiquette.

Should you invite the entire class?

You’re not obligated to invite the entire classroom if that doesn’t work for your family. According to Post, many families follow the “age plus one” rule. For example, a party for a 4-year-old should have five attendees.

Many schools even have set policies, like inviting half the class or less, or all of just one gender. If you’re not inviting everyone, it’s worth talking to your kid about discretion, says Post, and remind her that she should keep party talk to herself. And, if you’re planning to invite nearly the whole class, then you should invite everyone.

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Is it appropriate to send invitations via email or evite?

Though electronic invites can be convenient and budget-friendly, Post believes they lack one big benefit: They don’t allow your child to be part of the process. Opt for paper instead and you can let your child help pick out and write (or decorate, if he’s too young to write) the invitations. Feel free to use email to send out a party reminder.

How should you remind guests to RSVP?

Make sure you give a date by which you want RSVPs, and a method or two to reach you (a phone number is best, says Post). Then, one week before the party, call any families you haven’t heard from and say, “I wanted to call to see if Johnny was going to be coming to the party.

This is the time and date again. Please let me know – I’m just trying to get an accurate head count.” You’re not being pushy by giving a friendly reminder.

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Should you open presents at a party?

There are pros and cons. The benefits are that it’s good to teach your child about opening gifts and receiving graciously. Also, it’s wonderful for guests to see the joy and happiness their presents have brought. But little guests can get bored, and sometimes everyone wants to play with the new toy (which can get broken or lost).

If you do decide to open presents while guests are still there, it’s important to create order, says Post. Have everyone sit down and remind kids they’ll be getting their own party favors later.

Once presents have been admired, hide them away with a, “We’ll have lots of fun playing with these later.” Note: Even if your child does open gifts in front of his friends, he should still send a thank you note later.

What should you do if your kid receives an expensive gift?

Receive gifts with the same spirit of generosity in which they were given, says Post. Be grateful, and don’t consider refusing the gift because it’s “too much.” Instead, explain to your child that she received a very special present, and be sure to have her personally thank the gift giver.

When it comes time for that child’s birthday, don’t feel you have to reciprocate. Stick to your budget on presents, and don’t try to match gifts.

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Are goody bags a must?

“Goody bags were always a part of parties when I was growing up,” said Post. All the same, she says, they are not necessary, and giving them out depends on your party style.

Sometimes the most meaningful takeaway is one you’ve made, like sending guests home with homemade muffins, or cupcake liners filled with candies or balloons.

How much should you spend on a child?

There is no right number, Post says, it’s about giving something special to acknowledge the child’s special day. Spend what is in your budget. If that’s $10 per gift per child, work with that, but also ask his mom about his interests so you know whatever you choose, he’ll love.

Should your child help you pick out the present?

Since your kid is going to know what the other child would like more than you might, go for it. Plus, it teaches her about giving to others. For younger children, you could ask questions about what their friend might enjoy.

For example, try asking, “Does Susan like arts and crafts or playing with toy cars and trucks at school?” For kindergarteners and up, you can say, “We have $15 to buy Susan a present. What do you think she might like?”

If your kid is too young to understand, or is going through a “mine, mine, mine!” phase, then go pick out a gift without her and don’t worry about it!

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What if you can’t afford a present?

One option is to call the hosting parents to let them know. You can say something like, “Store-bought birthday gifts are tough for us to purchase right now. We were thinking of baking Kelly’s favorite cookie. What does she love?”

This lets the other mom know what to expect, and that you really care, without asking her what you should do. Of course, you also have the right to discuss the situation with your child and politely decline the invitation.

What if your child is invited to a party where she’s expected to buy something (like a costume or admission to an amusement park), and you can’t afford it?

You could DIY the needed costume yourself, which could be a great bonding project. If the party expenditure requires a specific dollar amount, it’s okay to decline the invitation and, instead, offer to have the child over a different time to celebrate over a homemade dinner, or with a small gift.

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If you have two kids, is it okay to bring the sibling to the party?

In general, it’s expected for a parent or caregiver to stick around during parties for infants and toddlers, says Post, and in our experience, even through preschool. After that, she suggests asking the host what they prefer.

If you have siblings to deal with, it’s inappropriate to ask if you can bring them along. Try to make other arrangements, or call the hosts and ask if they would be okay with you dropping your child off instead of staying.

That also allows them to say, “Why don’t you bring the whole family?” Even if you’d only be bringing a newborn in a baby sling, Post says it’s still proper to call the host ahead of time to give her a heads up.

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If your kid is upset because she wasn’t invited to a birthday party, what’s the best way to talk about her feelings?

If your child is not invited to a close friend’s party, it may be because that year the birthday child is only having a family party, a very small party, or only inviting friends from the soccer team, etc.

Validate your child’s feelings of disappointment, and help her learn to be the bigger person. Suggest that she invite her friend over to play some other time.

If your child can’t make it to the party, do you still need to get a gift?

Unlike a wedding where you are obligated to send a present whether or not you attend, you don’t need to send a birthday gift if you can’t be there. You may choose to do so if it’s your child’s best friend or someone who bought your kid a gift, but it’s not required.

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