On my first playthrough I made sure I picked up every kid, so the last few pairings were kind of forced. Consequences be damned. The first half were awesome, the second half were complete garbage.
Chrom-Sumia: Lucina and Cynthia were basically carbon copies of their respective parents. I didn't have a problem with it. Both got Aether.
MU-Cordelia: Morgan was a sort of inverse of my MU. Faster, but not as strong. Defense was equal, meaning pretty good for a Dark Flier. Severa was a damn monster. Paired up, they were untouchable. Both had Ignis.
Lissa-Frederick: Owain could hardly stand on his own at first, but in pairs he was really good. It took a while before he gained traction though he turned out ok in the end.
Sully-Virion: Kjelle turned out ok. She was a faster Sully, with decent defense. Not completely over powered, but not unusable.
Miriel-Lon'Qu: Laurent had a hard time to start, but once I found him a good partner, he was alright. Good defense for a mage. Plus Astra was shenanigans.
Vaike-Panne: As I was building their Support, they made a good pair. They handled Chapter 12 entirely by themselves. I figured their kid would be good too. Wrong. Yarne was a piece of crap. Weaknesses of both. Strengths of neither. Growth rate sucked.
Stahl-Maribelle: I kind of slapped this one together. Brady wasn't optimized, but wasn't entirely useless. Just not as good as he could have been. Demoiselle? Really?
Kellam-Cherche: I figured I would get a defensive unit with good speed. Instead I got a slow piece of flying tissue paper. Gerome was a disaster. If he survived long enough to hit anything, his damage output was awful.
Olivia-Henry: I used Henry just once before I started working on his support. I didn't use Olivia at all until then, either. Now I see why people pair up Olivia with Chrom. Even without proper training or an optimal paring, Inigo turned out to be pretty good. Strength was a little low, but no one could hit him. Plus he had Anathema. Paired with Owain, they could stand with my main units.
Libra-Tharja: Like a few of the other kids, Noire had a hard time to start. Paired with Laurent, though, she was alright. No replacement for any of my main units, but they worked.
Nowi-Gregor: Nah was completely ruined. Had worse stats than Nowi did when she was recruited. I couldn't get her off of the ground. She just wasn't good for me.
Notice I didn't pair anyone with Gaius. Well, I didn't know I could recruit him at first. Destroyed him in a single hit. It wasn't until three chapters later did I learn he could be recruited. At which point it was far too late to turn back.
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