This is an old one but I don't see it posted here so here goes:
There are 3 types of undergarments.
1)Boxers provide lots of room to breath but no support.
2) Briefs provide lots of support but no room to breath
3) Boxer briefs provide a bit of each - some support with some room to breath. Others argue that in attempting to provide both they provide insufficient of either - not enough support and not enough room to breath.
Similarly there are 3 types of Father in laws.
1) Some are like boxers and provide lots of room to breath (giving their kids space) but give you no support ($$).
2) Some are like briefs and provide lots of support but leave you with no room to breath.
3) And some are like boxer briefs with just enough support and just enough room to breath (or alternatively not enough support and a not enough room to breath).