If His word abides in our hearts and we abide in Him, we can ask whatever we want and He will hear and answer our prayers.
While we express to God our deepest thoughts and desires and the need for a specific answer, we can expect far more than our greatest imagination. We know God is working but what about those long periods of silence. Has God forgotten? No. There is nothing wrong with asking God for a sign that He is still involved. It is not an indication of weakness to touch base with God on the specific matter we put in His care. He is very willing to give us signs of encouragement along the way by demonstrating His love to us. The sign may not even be related to the thing we have trusted in Him for so long.
Sometimes after a genuine prayer concerning something very special to us comes an unexpected answer from the right person at the right time concerning another complicated situation. This is a sign from God that He works out all situations, even the ones we do not ask. These are the type of signs that are an encouragement that God has not forgotten any request. When we ask and are expecting to hear, it is exciting because it will be greater than our expectations. When we trust God and let Him bring the sign of His choice there is a glorious surprise along with the excitement.
Again the Lord spoke to Ahaz, “Ask the Lord your God for a sign, whether in the deepest depths or in the highest heights.”
But Ahaz said, “I will not ask; I will not put the Lord to the test.”
Then Isaiah said, “Hear now, you house of David! Is it not enough to try the patience of humans? Will you try the patience of my God also? Therefore the Lord himself will give you a sign: The virgin will conceive and give birth to a son, and will call him Immanuel.