Elon Musk Fathers 14th Child, Fourth With Shivon Zilis

Seems Elon Musk is truly going to colonize Mars ... even if he has to do it himself, 'cause the tech mogul just welcomed his 14 child!

Elon helped break the news Friday along with Shivon Zilis, with whom the billionaire already had three children.

SZ made the announcement on X, naturally, saying ... "Discussed with Elon and, in light of beautiful Arcadia’s birthday, we felt it was better to also just share directly about our wonderful and incredible son Seldon Lycurgus. Built like a juggernaut, with a solid heart of gold. Love him so much ♥️."

She did not reveal when Seldon was born or any other deets.

Musk simply replied to Zilis' X post, "♥️" ... which, given the other baby momma drama he has been in lately, is a pretty big deal.

As TMZ previously reported ... Ashley St. Clair sued Elon last week, requesting sole custody of the child she alleges they had together, who goes by R.S.C. ... who Elon has yet to publicly acknowledge as his.

The 26-year-old claims Musk wanted to keep the baby news quiet ... and she alleges Elon has seen the baby boy only three times since the child was born sometime in September.

Ashley makes it clear in her suit Elon has had nothing to do with the baby's care and upbringing ... and recently told TMZ Elon has allegedly ghosted her completely since she went public with the baby news.

And if that weren't enough baby mama drama ... around the same time as the lawsuit, Musk's former partner and mother of three of his children, singer-songwriter Grimes, pleaded with him on X to stop ignoring their child's "medical crisis."