Diary Reports of Concerns in Mothers of Infant Siblings of Children with Autism Across the First Year of Life.

Cox et al. (2015) asked moms of baby siblings of autistic children to keep a simple diary. Each week they wrote down any worry about language, social play, or odd repeated actions.

The team read the diaries when the babies turned 6 and 12 months old. They wanted to see if mom worries matched what the babies actually did at home.

Moms of high-risk babies wrote more worries than moms of low-risk babies. The gap showed up as early as 6 months and stayed clear at 12 months.

By 12 months, the diary notes lined up better with real baby behavior and family stress. Earlier, at 6 months, the match was weaker.

McGarty et al. (2018) extends this work. They tracked the same kind of babies for two full years and found that parent checklists at 6 months predict which babies will follow the slowest language path.

Gordon et al. (2015) used a similar design but counted gestures instead of diary notes. Both studies link early communication red flags to later autism risk, giving you two cheap tools: count gestures or read mom notes.

Older work by Rojahn et al. (1994) and Baranek (1999) used first-birthday home videos to spot autism signs. R et al. shift the lens earlier, showing parent diaries can catch worries before the first birthday cake.

You now have a low-cost early warning system. Hand mom a simple weekly diary at the 6-month visit. If she keeps noting language, social, or repetitive-play worries, schedule a follow-up and start tracking milestones. The diary adds no clinic time and may buy months for early intervention.