"I silently followed her and saw how, in a few minutes, the baby's body moved more and more slowly while the mother was singing an undefined melody, until the baby was definitively satisfied and surrendered to sleep," said Cesari, who is based in Bologna, Italy.
It was a magical moment, she said, one where she saw mother and child physically and psychologically reunite in a place just for them, "their moment, their space, their room," she said.
But behind her camera, she was able to join them. Those quiet moments of transition -- from awake to asleep at a mother's breast -- inspired her series "In the room."
It began in 2013 and continues even now. At first, she focused on the physical contact between moms and babies. Later on she refreshed her gaze, she said, trying to show women in the context of their spaces to avoid mistaking claustrophobia for intimacy.
Cesari has photographed friends, acquaintances and sometimes women she met just for the project. Patience and improvisation were required. She needed a keen eye to use natural light in dark rooms, to avoid piles of toys and baby gear, and to look past the curious stares of big brothers and sisters.
For each session with a mother and child, Cesari might spend two or three hours, capturing whatever peace or plunder unfolds.
"The baby doesn't fall asleep, or enjoys sucking too much, ending up regurgitating everything, a total disaster," Cesari said. "Nevertheless, in those cases, I don't necessarily go on forever to get the perfect moment. It's more important not to add tension to an already delicate situation."
Cesari breast-fed her son till he was 9 months old. It was a positive experience she said, but there are few photos of her, if any. She was living in the moment, "loving it deeply and hating it sometimes."
The women she met for her project have been jubilant and optimistic and sometimes exhausted or even depressed. She catches them in moments that can be sweet and tender or painful and frustrating.
Cesari wants people to see the amazing strength they have as mothers. However tired, worried or shy they felt, what they communicated was pride and confidence.
It was "an incredible proof of the transformation they were going through," Cesari said. "In the photographs, the main characters are not the babies but the mothers, caught in the moment they accompany their child to sleep."
Cesari said she looks back on the exhaustion, monotony and uncertainty of early motherhood with empathy and, now, appreciation.
"It has been an amazing privilege to witness moments of such intimacy," she said.