I agree with Kimberly, I don't think it sounds like SA but that she's used to seeing you and getting a cuddle in the night. If she's doing a mantra cry, then definitely leave her be, as annoying as it may be. Don't go to her unless she's crying-crying, and if that happens then try and soothe her in the crib without picking her up. Or, you could go with PU/PD as well.