Help me out

So I really want to make a will and I have 1 kid and another on the way. Idk who I’ll have take them if me and their dad both die before theyre 18. We only have 2 people we could trust with our kids which are my sister and his sister.

We’re not really too close with his sister like we’ll see her once a month or so and talk on Facebook a little. I like her a lot and she’s a good mom to her 2 children. She makes a lot of money so I know my kids would be taken care of financially, it’s just like I said I’m not too close with her so that’s weird to me.

My sister we see 3-5 times a week. My son loves her and I know she loves him. She makes like $50 a paycheck and is pretty irresponsible with money but I feel like if she had a kid to take care of she’d be better. She’d raise him how I would so that makes me feel like I should choose her but at the same time I don’t want my kids growing up poor as shit like I did.