Honor your father and mother, which is the first commandment with a promise (Ephesians 6:2).
Mother's Day for Missionary Moms is a difficult day. The sermon for the assembly of the gathered saints is focused on Moms and Grandmothers and Great Grandmothers. Often moms are asked to stand and be recognized by the congregation. After corporate worship children take their moms out to eat, but not you. Your children and grandchildren seem a million miles away. Oh, if they know it is Mother's Day in the States, they will call you or Skype you if they can. They may have already sent an email and email card, but you dread the inevitability of the day. It's another tough reminder that your children are missionaries - not that a day goes by that you don't remember.
Mother's Day is the day children are to spoil their mothers. Images of breakfast in bed or the gift of flowers and chocolates play across tv screens. It is subtley intimated that the number of gifts and cards a mom receives, equals how much she is loved. If you are also taken out to eat, you are really loved.
Mother's Day could become a miserable day for you. I don't know if this will help you or not, but this is a way I cope with special days I can no longer celebrate. My anniversary comes up every year, but I am a widow. My son's birthday, like clock work shows up every February, but he has been with the Lord longer than he lived. What do I do with those days? I celebrate them. I invite a friend out for dinner and I pay the bill. On those days, I even order dessert. Those days are very special days and instead of mourning, I rejoice that I was married for 43 years to a wonderful guy who loved me back and that I was allowed to be the Mom to a special son for 21 years. On Father's Day I will see that my son-in-laws get special cards and I will celebrate. My suggestion is that you celebrate this Mother's Day and rejoice that you are a Mom. Invite another Mom who will be alone also and go out to lunch together. Wear a special dress. Give yourself permission to have fun. Look for the people in your congregation who will be alone and be sure you hug everyone of them. Choose not to mope. Look and list things you are thankful for and remember, on the last day, someone may come up and hug you because your son or daughter lived Jesus before them and so they listened to their words about Him. They will thank you for your sacrifice.
It is far better to know that you will spend eternity with your missionary son or daughter than to have them home for Mother's Day this year.