So, I mention it in various stories plus my One Shots book, but the characters do have kids.

Ace & Aoi have a son named Rogue, and a daughter named Rose. Both named in tribute to Portgas D Rouge, Ace's mother.

Law & Aka have a Daughter name Lami and a son named Rocinante. Lami, of course being named for Law's sister, Lami and Rocinante being named for Aka's father, Donquixote Rocinante.

Zoro & Ki have twins, a boy name Kosen and a girl name Kuina. Kuina gets her name from obvious places and as for Kosen, well, Kosen was the name Ki's mom was going to name her if she was a boy.

Luffy & Aisuru, I know, you're shocked that they have a kid, but they do. They have a daughter named Ashe. Named for Ace. Luffy actually asked Aisuru to name the baby after Ace if it was a boy, however, the baby turned out to be a girl, so Aisuru figured Ashe was the closest girl's name to Ace.

Sabo & Ginger have a Daughter named Tatsu and a son named Mace. Tatsu is named after Dragon. "Tatsu" is actually a common name for female Dragons. Mace is named in tribute to Ace. Also, Ginger was named after the spice ginger and Sabo basically went "fuck it, let's keep the spice name trend" and yes, mace is an actual spice.

Marco & Yatsumi have a son named Pheonix and a daughter named Viviane. Yatsumi has a fascination with mythology, so she decided to name the kids after mythological beings and/or creatures and Marco didn't protest at all.