A legal defense fund has been established for Michael Flynn to help the former national security adviser pay his legal bills amid multiple investigations related to the 2016 election.

Flynn’s brother and sister, Joe Flynn and Barbara Redgate, are operating the fund, which began accepting donations early Monday morning.

The fund, which has been in the works since July, is being established to help Flynn’s family cover the “tremendous” legal bills he’s racked up since coming under investigation for his business activities during the presidential campaign, the fund’s website states.

Flynn’s legal expenses are expected to reach well into six-figure territory.

“The various investigations arising out of the 2016 presidential election have placed a tremendous financial burden on our brother Mike and his family,” Flynn’s siblings said in a statement issued through the retired lieutenant general’s attorney, Robert Kelner.

“The enormous expense of attorneys’ fees and other related expenses far exceed their ability to pay. To help ensure that he can defend himself, we have set up a legal defense fund, and we are asking Mike’s supporters, veterans, and all people of goodwill to contribute whatever amount they can to this fund.”

Flynn served as national security adviser to President Donald Trump for 24 days before being fired on Feb. 14. The official reason for the firing was that Flynn misled Vice President Mike Pence about discussions he had with Russian ambassador Sergey Kislyak in December.

Though Flynn was not accused of doing anything illegal by speaking to Kislyak, he allegedly told Pence that he did not discuss sanctions with the Russian diplomat. He also reportedly denied to FBI investigators that he discussed sanctions, though he later acknowledged that he may have discussed sanctions.

While Flynn’s interactions with Kislyak have caused headaches for him and the Trump White House, it is Flynn’s business consulting work during the campaign that may end up being his biggest legal obstacle.

Last August, Flynn Intel Group, Flynn’s consulting firm, signed a $600,000 consulting contract with a Turkish businessman with close ties to the Turkish government to investigate a political opponent of Turkey’s president, Recep Tayyip Erdogan. (RELATED: Flynn Is Lobbying For Obscure Dutch Company With Ties To Turkish Government)

Flynn Intel initially disclosed the lobbying work to Congress in September, but did not disclose the affiliation to the Turkish government or the massive size of the contract. In March, after months of discussions with the Justice Department, Flynn retroactively registered as a foreign agent of Turkey. (RELATED: Lobbying Disclosures Reveal The Next Scandal That Would Have Hit Michael Flynn)

Special Counsel Robert Mueller and the Senate Intelligence Committee have keyed in on Flynn’s business activities.

Mueller, who is conducting a sprawling investigation into Russian meddling in the presidential campaign, has reportedly used a federal grand jury in Virginia to subpoena Flynn’s business records and those of his former Turkish client, Ekim Alptekin. Mueller has reportedly asked witnesses questions about whether Flynn gave kickback payments to Alptekin, the chairman of the Turkish-U.S. Business Council, a trade group controlled by the Turkish government. (RELATED: Mueller Looking Into Whether Flynn Made Kickback Payments In Turkey Contract)

Flynn’s legal defense fund will accept donations only from U.S. citizens and permanent residents, according to its website. Anonymous donations and donations from the Trump campaign and Trump Organization will also not be accepted, The Daily Caller is told.

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