Cromdo, a Dad?
Who's the mom? I dunno. The little ones probably don't either. Shar is younger, but Marth doesn't mind that she's bigger. He's more chaotic and does most of the running off, whereas Shar follows him to make sure he doesn't die. My head cannon is that he got divorced after repeatedly trying to use the kiddos as a sales tactic, but the other didn't really want to take care of them either. He had grown a soft spot to them, despite pretending he didn't care for a long time. He smuggled them to Snaktooth, but didn't tell anyone, because he quickly realized it would be very frowned upon that he brought a couple grumplets (officially what I'm going to call you g grumpuses now oml it's so cute) to an island that transforms you. Thankfully, somewhat out of greed and somewhat out of caution, he gave the kids sauce and anything other than bugsnax to eat.
And no, the mom/his partner is not one of the original cast in my hc! Please don't ship him, lol, but you can draw what you think the mom/partner looks like, as I'm not sure when or if I will.