Babies may use saliva sharing to figure out relationships
Actions like sharing bites of food or kissing may cue young children into close bonds
![image of parents laying on either side of an infant and kissing the infant](https://i0.wp.com/www.sciencenews.org/wp-content/uploads/2022/01/011922_eg_baby-spit_feat.jpg?fit=1030%2C580&ssl=1)
Children as young as about 8 months old keep tabs on who shares saliva, using it as a marker of who may be in a close relationship and who isn't, a study suggests.
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