curl --request GET \
  --url https://api.example.com/staking/validators/{validator_addr}/delegations/{delegator_addr}

{
  "code": 200,
  "msg": {
    "delegation_response": {
      "delegation": {
        "delegator_address": "0xdb8e606ad7c02f37e43d10a10126791dc94b0434",
        "validator_address": "0xdb8e606ad7c02f37e43d10a10126791dc94b0434",
        "shares": "1000000.000000000000000000",
        "rewards_shares": "1000000.000000000000000000"
      },
      "balance": {
        "denom": "stake",
        "amount": "1000000"
      }
    }
  },
  "error": ""
}