Originally Posted by seacarl

I believe you will only have access to the Senator Lounge in FRA on your way to India. On your return to USA, you will be entitled to use the LH FC lounge. Be aware that there is no FC lounge in the Z concourse, which is where UA will depart. If you arrive in the B concourse, there is a LH FC lounge there which you should be able to use. Alternatively, pass through German immigration and go to the A concourse (which is directly below the Z concourse). There is a LH FC lounge on the A concourse. Generally the passport lines are short so it should be worthwhile.

No car service is available to UA flights - but they almost always board at proper gates. I don't know whether LH may turn a blind eye to your 2-year-old. I believe that generally the GS member is not entitled to bring any guests