### Is there any chance you could renegotiate her contract?

You don't have to threaten her with *firing*. Just give her the option of a contract with more flexible hours at the cost of a small pay cut... aiming for a sweet spot that is as small  as possible (to avoid harming her ability to raise her family) while large enough to prevent others from feeling jealous.

If you want (this is optional), you could then even entice her to stick to more regular hours by correlating her bonuses to that. It'll be a positive reward instead of a negative punishment.

And when people start being inquisitive, now you can get the message across that she's no longer bending the rules (but make sure to let her know this before the renegotiation, so she understands your side of the situation in case she gets questions herself):

> No, her contract has changed a bit, so her hours might be slightly shifted from now on.  
We decided in her particular situation it makes sense to renegotiate a modified contract and compensation to better accommodate her constraints.  
Please consider these changes permanent moving forward, and if any related issues come up, just reach out to me and I will handle them. Thanks.