Paid sick leave is not governed by law--the law does not require paid sick leave. It is voluntary for employers to provide this, and so it is governed by the employer's policy in regards to leave. If your employer allows you to use your sick leave for this purpose, you can do so; but if they do not, you cannot. If you have an employment or union agreement which addresses sick leave, look to its provisions--to the extent they address this situation, they will control.