Who looks after your kids when you're at work. Have you asked other family/friends who know your situation better their advice. Does your dad have anyone else he could get help from, any siblings in his family or partner/wife?
Maybe a centre for seniors where he can go for a day or two? I could offer ideas for him, but it's dependent on his health & activity level. Would you feel comfortable letting him know you want several days to recharge, little kids are a lot, mentally & physically. Hope it works out for you.
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