I saw a newspaper ad a week ago about a couple wanting to rehome a 7-month-old yorkie girl because they feel like they don't spend enough time with her and on top of that the wife is pregnant. She's AKC and UTD on all shots and from a reputable breeder in the area (according to the owners).
I've been wanting to adopt a sister for cocoster (he's 1.5 yrs old) for some time because I don't want him to grow up as an only furbaby. I even bought clothes for her already (how can I resist?

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BUT today I received most recent pictures of the little girl and she looks so grown up! Now I'm torn because I cherished every mimute of cocoster's puppyhood and I won't have that with the girl.

Am I being stupid?
First picture is cocoster and the second ones are of the girl. Do they make cute sister and brother?
Did anyone adopt an older puppy and feel sad about missing their puppyhood?