I am watching M3S for a second time through. I am noticing similar types of comedy between the two shows.

Mike's Brothers I noticed has Robbie falling down a lot similar to Bud falling down. Was this a common thing during the time period?

I remember the Bud falling routine got old VERY quickly as it seemed so unnatural. I don't think Rob "fell" quite as much. But now that I'm thinking about it, maybe he did. The slapstick falling routine can be funny IF it's done rarely and if it's the proper "victim" falling such as a dignified rich guy or a hoity toidy type poyson. But when its a kid falling every 15 minutes it just ain't funny cause you know he hasn't lost any dignity as he never had it to begin with. Comedy does have rules and not just anybody can do it.

Didn't both of these shows share one or more production personnel? I think maybe the director for the first season of MTS also directed many FKB.

Didn't both of these shows share one or more production personnel? I think maybe the director for the first season of MTS also directed many FKB.

Yes, Peter Tewksbury directed M3S as you mentioned, and seasons 3 thru 6 of FKB.