Should I apply for I-130 for my sister through me or my mother?

[Looking2Reunite]

Hi~ I'm in a dilemma:

I am a US citizen. I would like to sponsor my mother and older sister (unmarried, over 21) for US Permanent Residency.

The priority date for my mother is about one year out which isn't too bad. However, if I apply for my sister, USCIS said it could take 12 years for her to get the green card. Once my mother becomes a LPR, I think she can apply for my sister which would take slightly less time (about 7 years I am told). I am not exactly sure on the times but they seem awfully long. They are both citizens of a country which has very few people emigrating to the U.S.

Should I go ahead and apply for my sister anyway along with my mother or should I wait for my mother to get her GC and then apply through my mother?

[peace999]

The visa number wait times you have been given are correct.

It makes sense for your mother to apply under F2b( single children over 21 of PRs)
for your sis after she gets her GC. Which she will get in 10-12 mos.
As She is your immediate relative so there is no wait for her visa number .

Still, talk to a good immigration attorney if F4 ( siblings of USCs) and F2b can run concurrently and if later you can opt out of one.