Read stories about friends having fun together.
Chat to them to find out who their friends are and what they like to play with.
Arrange to go to soft play, messy play, outside fun, book bug etc with parents/grandparents and their children/grandchildren so you get to know children with their families and form relationships.
Grandson only 2 ½ so too young for playdates but these could be arranged when he is old enough.
Don't interfere too much but be aware of what is happening.
Words of 7 letters, (new) 2 changes allowed