The NY Post is reporting that J.Lo actually attended a mediation session in Miami between the two parties and participated in it.
It is understood that she believes that A-Rod stumps up too much cash to his former wife.
According to sources she believes he should pay Cynthia only $10,000 a month in child support.
He reportedly is paying $100,000 a month support for his young daughters Natasha and Ella.
A-Rod's estimated wealth is $400 million, so, Cynthia was blindsided by the new demands.
One source revealed that the singer was "driving the bus" and that the second day of mediation was postponed because negotiations got heated.
The sessions are confidential and neither Cynthia or her attorney, Maurice Kutner, would not comment on them.
Tellingly, though, she revealed recently: "Alex has dated some wonderful women since our divorce, many of whom have had positive relationships with our children.
"Alex and I have worked well trying to create a stable environment for our daughters and there has never been an issue. Until now."
Mother-of-two Lopez is known to be a very tough negotiator and she has been divorced three times, so, she knows a lot about child support and legal battles.
Cynthia, 45, has always used Rodriguez as her surname even after their 2008 divorce.
She got engaged to a Florida businessman involved in real estate and the fitness industry four years ago. The couple had a daughter two years later.
"Everybody got along," Cynthia said of the relationship between her fiancé and A-Rod early on.
"Everything was fine. This is all new."
Lopez and Rodriguez love to show off their flashy lifestyle on social media and they seemingly get along with singer Marc Anthony, who shares twins Emme and Max with J.Lo.
It had been reported that A-Rod pays Cynthia $115,000 a month but her lawyer says that this figure is not accurate.
However, he wants to get the payments reduced and it seems that J.Lo agrees and wants to be actively involved in any negotiations.
However, to make matters more complicated Cyntha's brotherConstantine Scurtis has filed his own multi-million dollar suit against A-Rod in Miami.
He has multiple claims against Rodriguez over multiple real estate deals that the pair at one time was involved with together.
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