Hollywood star Dennis Quaid is dismissing rumors that his ex-wife Meg Ryan is filing for full custody of their  teenage son Jack after media reports surfaced questioning his sobriety. The actor split from Ryan in 2000 and their divorce was finalized in  2001. The Hollywood couple, who share custody of 16-year-old Jack, has left Tinseltown  guessing over the details behind their breakup for the last eight years, but Ryan  finally broke her silence last week, when she claimed Quaid had cheated on  her.The news prompted sources close to the former couple to leak  further information about their divorce, with one insider claiming that their  joint custody agreement included a stipulation about Quaid’s sobriety, reports  the New York Daily News. The source says, "Meg came to believe he was  drinking again and wanted full physical custody of Jack." But Quaid has refuted  the reports, insisting nothing has changed in their care of their son since the agreement  was made. He says, "Meg and I have always had joint custody of Jack without  any stipulations whatsoever."Photo By: RD/Dziekan/Retna