请问 everyone 作主语的情况下 后面的代词用his 还是 their啊?如：everyone is concerned with his family 还是 everyone is concerned with their family?还是两种都可以?用法有什么区别吗?

请问 everyone 作主语的情况下 后面的代词用his 还是 their啊?
如：everyone is concerned with his family 还是 everyone is concerned with their family?
还是两种都可以?
用法有什么区别吗?