How I Met Your Mother: Are Lily and the mother separated at birth?

I didn’t notice this when I first saw the mother at the end of season eight of How I Met Your Mother, but upon reading more today I suddenly noticed that the actress who is playing Ted’s wife (Cristin Milioti) bears an uncanny resemblance to her new co-star Alyson Hannigan who plays Lily.

Is this just me noticing this? I’m sure it’s not deliberate but surely it’s a bit weird if Ted marries someone who looks like Lilly, his best friend’s wife.. The show is all about “how I met your mother’, it would seem a little weird for the mother to look like the kids’ aunt Lily. Just saying!