As you may have noticed that if you try to select more than 5 pictures in gallery at a time then share button gets disabled and you are forced to share 5 pictures at a time. To share more than 5 pictures at a time from picture gallery, go through following steps

Step 1. Keep on selecting pictures as many as you want

Step 2. Tap on copy button.

Step 3. Open mail window.

Step 4. Paste coped pictures as you paste any other text and send email to your loved ones.