After about a half hour of this, Max (age 3) walked by, and, knowing a good thing when he saw it, hopped onto my right leg and asked for trains. Minutes later Milo (age 5) came by. No lap being available he stood next to me and for ten minutes or so, I had 3 of my favorite people all huddled together wanting to play grandparent games. (Jonah (7 months) was somewhere else in the house.)
Eventually Mira had had it with the competition and uttered a few "mamas" and the party ended. But it was great while it lasted.