If you've been living behind a rock...or just haven't had a second to catch up on your TMZ news, you might have missed the latest in Usher's custody battle with ex-spouse Tameka Raymond. According to TMZ, Tameka was pushed to the brink last Monday, after the ex-spouse's 5-year-old son, Usher Raymond V, had to be brought to the ICU after his arm became stuck in a pool drain.

On Tuesday, following Usher Jr.'s injury, Tameka filed court documents in Fulton County, Georgia, seeking an emergency, or "ex-parte" hearing to review the existing custody arrangement. As it currently stands, Usher has primary custody of the ex-spouse's two children. Tameka, on the other hand, has only limited access rights.

Now, Tameka is claiming that Usher has been delegating his parental duties, preferring to leave the children in the hands of child care staff and family members, specifically Usher's aunt. Moreover, TMZ is reporting that Tameka questions the competence of her children's nannies and their father's ability to adequately care for the children.

According to TMZ, Tameka takes serious issue with the fact that Usher allows the children to be watched by his aunt, who was caring for Usher Jr. when the pool incident occurred. Tameka has long since disagreed with the aunt's physical discipline of the children, and even alleges that Usher's aunt let a stalker into the house where Usher and the children were staying. This week, the allegations became more serious with Tameka claiming that Usher Jr. was left unsupervised in the swimming pool.

However, it would seem that this week's events were a mere tipping point for the frustrated mother. According to celebrity blog sources, Tameka alleges that Usher is away from home 85% of the time every month and that he has hired irresponsible and inadequate staff to care for his children in his absence. She now seeks temporary primary custody of both children. A reversal of the current custody order would give Tameka decision-making authority over the children's education, healthcare, and religion.

Last August, following the tragic death of Tameka's son (and Usher's stepson), Usher was awarded primary custody of the couple's children. As is common in acrimonious spousal relationships where it is assumed that parents will be unable to parent together, the judge awarded only access rights to the non-custodial parent, Tameka.

How will this week's events affect Usher's ongoing custody rights? While it is difficult to anticipate a judge's reaction to such events, the judge will engage in an analysis of the children's best interests.

In Ontario, decisions concerning custody and access are determined solely on the basis of the best interest of the child. Section 24 of the Children's Law Reform Act outlines a number of criteria for determining a child's best interests, including:

• the love, affection and emotional ties between the child and their guardian;
• the child's views and preferences;
• the length of time the child has lived in a stable home environment;
• the ability and willingness of each person applying for custody of the child to provide the child with guidance and education, and the necessaries of life;
• the plan proposed by each person applying for custody of the child for the child's care and upbringing;
• etc.

Accordingly, while the judge must evaluate the importance of this week's events and how reflective they are of Usher's ability to care for his children, the judge will likely look at a host of factors in determining whether to vary the current custody order.