The 28-year-old US Olympic swimmer, who has won five medals in the pool including two golds at London 2012, was apparently unaware that parents Ileana and Steve owe over $242,000 (£155,000) plus interest on their home.
The couple are said to have taken out a $258,000 (£165,000) mortgage in 2007 but allegedly stopped making their monthly repayments of $1,609.58 (£1,034 approximately) after divorcing in February 2011.
CitiMortgage has apparently filed a lawsuit against the pair in order to foreclose on the house and get its money back.
According to TMZ, the company also wants the former couple to pay any outstanding balance themselves if the sale of the house does not cover their debt.
Ileana previously made headlines after commenting that Ryan only "goes out on one-night-stands", which the athlete later denied.
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