One US study suggests around 15% of siblings have had conflicts over money
Do your parents have a favourite child and give them more money, gifts or help?
Financial favouritism can cause jealousy and resentment long into adulthood and, in some cases, even spark legal disputes after a parent dies. But experts say there are strategies that can help you avoid it.
John says his parents, who have always supported his younger brother, recently refused to lend him £10,000 towards a house deposit after he broke up with his partner.
This was despite the money being "well within their financial grasp", he says.
His parents had previously given his brother a deposit to buy a home and subsidised his living expenses.
John, 47, whose real name we have changed, says he was viewed as the more academic one growing up and expected to stand on his "own two feet" financially, while his brother, 42, struggled to make his way in the world and was "coddled".
He says the favouritism has made him believe "the needs of others take precedence over my own", leaving him feeling "isolated" and affecting friendships and romantic relationships.
Forums like Mumsnet and Reddit, external are full of posts complaining about siblings being shown preferential treatment regarding money.
Common gripes include the amount of financial support adult children have received, external from their parents during their lifetime, the way inheritance is divided, external, and whether a sibling has supported their parents more than others, external.
Dr Fenia Christodoulidi, from counselling service Relate, says that disagreements about money between siblings are rarely just about the money itself.
"Financial support from parents often carries a powerful emotional meaning and some siblings tend to interpret differences in support as signs of favouritism, unequal love or a lack of recognition."
She adds that even when parents have "practical reasons" for treating their children differently, failing to communicate these clearly can "leave room for misunderstanding and resentment".
Those reasons might include an adult child needing more support because they earn significantly less, have an illness, or have to pay more to get on the housing ladder due to rising prices, external.
Ellis, 26, says there is no financial favourite in her family
