That’s an intense, emotionally charged piece — it reads like a psychological family drama with betrayal layered on betrayal.
Structurally, it works well as a suspense short story because:
The slow build-up (starting with a seemingly innocent offer from the mother-in-law) makes the reveal more shocking.
The “friend” mystery is maintained until the midpoint, so readers are invested in figuring out who it is.
The hidden camera device serves as a pivotal turning point, which is a satisfying payoff to the mounting suspicion.
The confrontation scene is direct, emotionally raw, and establishes the stakes: custody, trust, and betrayal.
The ending resolves the immediate threat (cutting Cheryl and Alexa out) but leaves lingering tension about Jason’s loyalty — which keeps it realistic.
If you wanted to make it even more gripping:
Foreshadow Alexa earlier — maybe through a stray comment from Jason or a photo Beverly finds — so the reveal hits with both recognition and shock.
Tighten Cheryl’s motive — her desire to “replace” Martha could be hinted through passive-aggressive comments or overstepping boundaries before the big reveal.
Give Jason a harder choice — if he briefly hesitated before siding with Martha, it could add realism and drama.
Use sensory detail — describe voices lowering, eyes darting, subtle movements — to heighten the tension in key moments.
It already has strong emotional stakes and a clear narrative arc, so with a bit of sharpening, it could easily work as a short story in a domestic thriller anthology.