practice sports, PE classes, swimming clases, reading, play date with friends
I think the experience, certifications, availability,
I personally will show them good arguments or benefits to do that.
It will depend on experience, certifications and what do they expect
singing, play same instruments (like guitar, flauta, violin, piano), go for a walk with stroller, swing at the park...
I probably will do it.
First at all you should always be an example to them, at that age they are very observative, if you ask them to do something but you don't do it, they will be confused and probably they won't trust you.
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