President Donald Trump's financial disclosure forms shed light on his entire family's financial holdings.

Both of Trump's 2018 and 2019 forms included disclosures for an apartment in Trump Tower owned by first lady Melania Trump.

The first lady apparently purchased it in January 2016, but the one-bed, 1.5-bathroom apartment has largely remained a mystery since.

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The Office of Government Ethics has released President Donald Trump's 2019 financial disclosure form.

These forms reveal much about Trump's finances — including the reimbursement of the hush money his lawyer Michael Cohen paid the adult-film actress Stormy Daniels — but the form also provides insight into first lady Melania Trump's income.

Two of her disclosures were related to a one-bed, 1.5-bath apartment in Trump Tower in Manhattan that Melania bought from the building's condo board for almost $1.5 million in January 2016, according to The Real Deal and City Realty.

Here is everything we know about the mysterious apartment the first lady owns in Trump Tower.