At five months, I would not give up. Tate's ears were up for quite a while before he started teething, then they went down. For a couple of months they would go up, down, up, down until they finally started staying down. Two weeks ago, I decided to clip all the hair off his ears - all the way to the base. It looks funny, but within a day they were standing straight up and they've been up ever since. He's 7 1/2 months old now! Good luck!
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He is your friend, your partner, your defender, your dog. You are his life, his love, his leader. He will be yours, faithful and true, to the last beat of his heart. You owe it to him to be worthy of such devotion. -- Author Unknown