My Dad is starting to take care of a baby doll at daycare. Are we suppose to take this up with him at home?

When my mom picked my dad up from daycare today, he had a baby doll in a wheelchair and the caregivers that had watched over him today told her that he had been so sweet today and that he just pushed it around most of the day and took real good care of it and then they told him that it would be ok, that they would take good care of it until he comes back. My question is should this just be a daycare thing or should we get him his own baby doll and play along?