A Long Island woman who vanished last month in Manhattan along with her 14-year-old daughter is in the midst of a vicious battle over her late husband’s estate.

Iona Costello, a 51-year-old farm owner, is fighting her late husband George Costello’s four children from a previous marriage over the fortune he gained from owning a construction company, according to court records.

Iona, 51, vanished with her daughter Emily last month after what relatives thought was going to be a trip to Manhattan to see a Broadway play.

Their car was found in a parking garage on 42nd Street last week. Surveillance video from the lot showed them laughing and carrying suitcases.

Relatives filed a missing-persons report when Emily didn’t return to school on Tuesday.

Iona’s mother, Diana Malcolmson, said stress may be the reason why she took off without alerting anyone.