Oldest with Youngest This pairing has some good mojo behind it: The youngest child is cared for, while the older sibling can exert control.
Take that into consideration and make compromises to keep the relationship solid.
This can be a fine pairing most of the time, but the middle child's tendency to mold herself around her partner may leave her in danger of not following her own dreams.
That's because middles morph into the styles of the other types, depending on the dynamics of their particular family, says Dr. A middle child with a much younger sib may act more like a lastborn (and the opposite situation may make the middle more like a firstborn).
Relationship Tip: Try to suss out whether you have controlling tendencies (which you should keep in check so you don't overwhelm your younger-sib spouse) or if you both are acting like "babies."Youngest with Youngest These two can have a lot of fun—a pair of carefree, risk-taking lovers nearly always do.
Relationship Tip: Try to figure out which of you is best at certain tasks (such as handling money or making decisions about the children), and then own up to that responsibility, rather than assuming the other will take care of it.
Onlies with Anyone Unlike the other birth-order positions, only children haven't been studied as much, says Dr. "Most people assume an only child will resemble a firstborn in relationships," since they are, after all, first, but that doesn't take into account the fact that an only never had an advisory (or bossy! An only with a firstborn can be a good match if the only child acts less classically "firstborn." And an only with the lastborn can present issues, says Dr.
That said, they can be predictable in the best sense of that word.
"Middleborns are the Type O blood of relationships: They go with anyone," says Dr. As a general rule, middles tend to be good at compromise—a skill valuable to them as they negotiated between bossy older sibs and needy younger ones.
Says Cane, "Firstborns like to be in control." As with all birth-order positions, gender plays a role, too.