Free plan — no card required
Two kids.
One timeline.
Finally.
Sibling Stack shows both your kids' sleep and feed windows side by side — so you can see conflicts before they catch you, not after. Built for the specific chaos of two kids close enough in age that their schedules actually overlap.
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Start With the Complete Guide
What "Irish twins" actually means, what's genuinely hard about kids close in age, what's genuinely good about it — and every schedule, tool, and guide on this site, organized by what you're dealing with this week.
Read the Complete GuideHow it works
Add your kids
Set up a profile for each child with their name and birth date. Sibling Stack works whether they're three months apart or three years apart — the scheduling challenges are real either way.
Log as you go
Tap to record sleep, feeding, and diaper changes throughout the day. Each event is timestamped and color-coded per kid so you can see at a glance who did what and when.
Spot conflicts before they hit
Both timelines appear side by side on one dashboard. When a nap window overlaps with a feeding, the conflict is highlighted visually so you can plan around it instead of getting caught off guard.
Everything in one place
Dual-timeline dashboard
Both kids on one view. See where sleep and feed windows collide the moment you open the app, not after the chaos starts.
Conflict detection
Every overlap is flagged and bridged visually between the two lanes so the pattern is obvious even at 3am.
Trend reportsPro
Is the shared nap window growing or shrinking week over week? Trend reports surface the change before the schedule breaks.
PredictionsPro
Based on both kids' real patterns, not generic advice — with honest confidence, never false precision.
Guides, gear, and free tools
Pick a lane — articles, schedules, gear, or a free calculator.
Articles & Guides
Nap schedules, feeding routines, sibling jealousy — the reading lane.
🍼Schedules & Routines
2-under-2, nap sync, dueling naps — shareable schedule templates.
🛒Gear & Strollers
Double strollers, car seats, carriers, and what you don't need to buy twice.
🧮Free Calculators
Wake window, nap sync, and bedtime stagger — free and instant.