GERD related or genetic disorder?

My 9 month old has suffered from reflux since she was born. She began having severe arching after feeding--it appeared she was having a seizure, her body would severely stiffen with her head arched back and to one side. Afterwards her head would be tilted, she would almost look like a horseshoe, like her spine was bent in the process. Her ped. said she had torticollis. She continued to get torticollis off and on and now has a slightly larger than pea sized knot on the side of her neck. Her vomit came out through her nose right before these "siezure-like" episodes would happen. Or sometimes it would come out her nose right after an episode. She went to a gastro doc and had the upperGI which confirmed reflux. She was put on 15 mg of prevacid. She doesn't have the 'episodes' anymore and so I thought the torticollis would disappear. However, it tends to come and go. It always comes while she sleeping, she'll wake up 'tilted' and remain so for a few days and then it goes away. She is delayed. She HATES being on her tummy and will immediately roll to her back, and gets in the "rolling position" as soon as she realizes I'm putting her on her tummy. She will NOT roll from back to tummy. When she sleeps she doesn't move. She stays on her back and keeps her head strait with her head tilted upwards. As a result has a nice flat spot on the back of head...She has just now begun sitting up and is still quite wobbly. She has a decent weight, not chunky but also not too thin, but didn't gain (or lose) at all last month. Her doctor is concerned about the torticollis and her muscle tone. She tends to remain stiff, like she's trying to avoid moving her injured neck muscle (her physical therapist suggested this). She keeps her arms up and to the sides and doesn't do much midline play. Her ped. is sending her to a geneticist to see if there is anything genetic going on. She's been to a neurologist twice who has found no seizure disorder to explain the "episodes." He also tested for some metabolic disorders which came back normal. My question is, could all this be GERD related OR do you think there could be something genetic going on? I'm at my wit's end with specialists, none of whom seem to care about "connecting any dots" but rather seem concerned about only treating or ruling out their specific "specialty." The neuroligist ignores the whole reflux part. The gastro doc ignores the whole "episode" part. Maybe the gentic doc will tie them all together... Also she has weak ankles and her right foot turns in slightly. Ped is considering a brace to strengthen and straighten it but said it doesn't look too bad too her right now. It seems this may delay her even more... She's not fussy at all, never has been. She's ALWAYS slept through the night and rarely cries, she's a happy baby. Which boggles me even more--considering everything she deals with. Any suggestions?  BTW, her 10 year old sister was diagnose with GERD via upperGI 2 years ago.  She has battled weight problems (she's only a size 7/8 slim at almost 11 years of age!), weird vomiting issues (cyclic vomiting syndrome), migraines, severe bad breath, strabismus (weak eye muscles), coughing fits every morning, and is easily irritated.  Don't know if this is relevent or not...  She was a difficult baby though--always fussy, always crying, woke up several times a night until she was 4 and still wakes up occassionaly to complain of tummy aches and migraines. Ava has a totally different "easy going" personality, where Allie (the 10 year old) is very tempermental and hard to get along with.  Is GERD itself genetic?