I realize that as a mom of 7 with my oldest almost 20, I don't play with the present toddler the way I used to with his older siblings. Because of his place in the family as the much younger sibling with the next one up being "special needs", he sometimes doesn't get the peer play that the oldest three or four got just by virtue of their place in the lineup.
I played with him for about an hour this morning. The technical jargon is floor time and it means simply interacting with the child on a playful basis with no overt agenda. Though it is possible to informally take the play a step or two further, so in that context it is useful for autistic and other kids who haven't learned to play naturally. It is also useful for "tying strings" but all this is an attenuated way of describing an interaction between two people who care about each other.
The present habit I am working on is to cut back on the babies' screen time. So playing with them has that motive, too. Plus, I am starting a system of toy rotation to preserve the integrity of our toys, and so when the babies are at loose ends, I can get out the toy and interact with them for a few minutes.