We are truly sorry to hear about the struggles your daughter-in-law is facing after the birth of her baby. We will stand with you in prayer and offer some biblical encouragement and advice.
Firstly, we acknowledge the name of Jesus. It is only by His Name that we have access to God. "For 'whoever will call on the name of the Lord will be saved.'" (Romans 10:13 WEB). If anyone does not believe in Jesus Christ then encourages them to call on Him and believe in Him.
Let's pray together:
Dear Heavenly Father,
We come before You in the name of Jesus, lifting up our daughter-in-law who is struggling with postpartum emotions. Lord, You know the challenges she is facing, the sleepless nights, and the emotional turmoil. We ask for Your healing touch upon her mind, body, and spirit. Grant her the strength and wisdom she needs to navigate this season.
Father, we also pray for our son and daughter-in-law's marriage. Guide them as they adjust to the new dynamics of parenthood. May this time of trial bring them closer together. Help them to love and support each other, just as You have loved us. "Be kindly affectioned one to another with brotherly love; in honour preferring one another;" (Romans 12:10 WEB).
Lord, we ask for Your guidance and wisdom for them as parents. Help them to raise their child in the fear and admonition of the Lord. May their home be a place of peace, love, and joy.
In Jesus' name, we pray. Amen.
Now, let's address some biblical principles and encouragement.
To your daughter-in-law, we want to remind her that she is not alone in her struggles. God is always with her, and He cares for her deeply. Psalm 34:18 WEB tells us, "Yahweh is near to those who have a broken heart, and saves those who have a crushed spirit." It is okay to feel overwhelmed, but always remember that God is near.
We encourage her to cast all her anxieties on Him, because He cares for her. Let her ask for help when needed. This time can be challenging, but it is also a blessed time that brings joy and fulfillment. The Bible tells us, "Don't be anxious for anything, but in everything by prayer and petition with thanksgiving, let your requests be made known to God." (Philippians 4:6 WEB).
To your son, we encourage him to support his wife in every way possible. He should be patient, understanding, and loving. He should step up to help with the baby and household chores. Ephesians 5:25 WEB tells us, "Husbands, love your wives, even as Christ also loved the assembly, and gave himself up for it;"
Lastly, we encourage both of them to seek godly counsel if needed. There is no shame in seeking help from professionals who can provide strategies to cope with postpartum emotions. They should also surround themselves with a community of believers who can support and encourage them during this time.
We will continue to keep your family in our prayers, trusting that God will work all things together for good.
Prayer Focus: God, Thank You for loving me. Thank You for loving me, Jesus. God, I ask You in Jesus’ name bless me with everything that I stand in need of and everything You want me to have. Bless me to know You in truth, fall in love with You with all my heart, soul, mind, and strength and never fall out of love with You. Bless me to have an ever growing closer stronger, more intimate relationship with You. Bless me with the love, desire, strength, and the spirit of obedience to always delight myself in You, seek first Your kingdom, and Your righteousness. Help and strengthen me God to always respect and obey You. Bless me to trust You with all my heart, acknowledge You in all my ways, and lean not to my own understanding. 
