If this is a Roku tv, you can buy aftermarket universal remotes that will control both Roku tv's and cable boxes. Check out the Insignia line of universal remotes from Best Buy, they come in 3, 5, and 8-device models. With these remotes you could map the hulu and amazon keys under the cable box device. Press them will send the Roku tv to those channels, but your mom would still have to press the TV device to navigate in the channels.
The Roku tv remote code is 4398. The cable box would be under STB device. The Hulu code is 00131, amazon 00156. To map them in the cable box device:
1. tv device
2. press and hold SETUP for two blinks, release
3. enter 9 9 4
4. tap SETUP for one blink
5. enter 0 0 1 3 1
6. press STB device key
7. pick unused key, like the green button for HULU.
Repeat but use code 00156 code in step 5, and pick a different color button like blue for amazon in step 7.
The 5-in-1 is on sale:
Insignia™ 5-Device Backlit Universal Remote Black NS-RMT5D21 - Best Buy
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