It is necessary to be all 3 founders present?, Can he still join you and work from home?.
I'm father of 2 and can't drop my job till I have a MVP and some founding (and then I'll only drop for a year or so)but this is not going to stop me any time soon.
If he is interested and a good fit why not trying working at distance?.
I also have problems currently with technical cofounders, It seems in Spain nobody wants to try a start up. Mind you I'm not asking them to drop their job.