To provide a working definition of neglect and abuse, it is defined as "any non-accidental behaviour by parents, caregivers, other adults or older adolescents that is outside the norms of conduct and entails a substantial risk of causing physical or emotional harm to a child or young person. Such behaviours may be intentional or unintentional and can include acts of omission (i.e., neglect) and commission (i.e., abuse)." [1]
With regards to LGB+ and Transgender youth, there is strong evidence to conclude that rejection, by family, and particularly parents, has severe impacts on the positive life outcomes and mental health of the youth. This impact can either be positive if parents are supportive or accepting, or negative if parents are un-supportive or rejecting.
"[H]ow families respond when youth come out during adolescence can have a powerful impact on young people’s health and well-being...Family connections have been shown to prevent major health risks and are a critical foundation for general well-being for all children...how they react and adjust to their children’s coming out can have a dramatic and compelling impact on their LGBT children’s health, mental health and well-being. LGBT young people whose parents and caregivers reject them or try to change them are at high risk for depression, substance abuse, suicide and HIV infection. And LGBT young people whose parents support them and stand up for them show much higher levels of self-esteem and greater well-being, with lower rates of health and mental health problems." [2]
These negative impacts can carry on into adulthood, with "LGB adults who reported high rates of parental rejection in their teens were 8.4 times more likely to report having attempted suicide, 5.9 times more likely to report high levels of depression, 3.4 times more likely to use illegal drugs, and 3.4 times more likely to have had unprotected sex than LGB peers who reported no or low levels of family rejection." [3] These findings are continually supported by other studies, whether specifically LGBT+, transgender, or otherwise. [4]
This is of course, not all the data which could be presented, but I'd like to keep this at a bearable length.
My Two Cents is that it most certainly should be considered a form of child abuse. It is clear time and time again that this is something which is extremely detrimental to the mental health, and positive life outcomes, of LGBT+ youth, and is definitely significant enough for this to be considered a type of abusive treatment.
Parents and families must be educated and taught that, regardless of their opinions on their child being LGB+ and/or Transgender, regardless of any 'sincerely-held beliefs' on the topic, they do not have authority or control over this aspect of their child's life, and that it is not appropriate for them to reject, try to change, or treat differently, their children for this reason.
Trying to change, or rejecting, a child because of their sexual orientation or gender identity, has every reason, from everything I can tell, to be considered a form of child abuse.
