diff --git a/cmd/mstdn/cmd_stream.go b/cmd/mstdn/cmd_stream.go
index 1ba9a6c..1b83d1a 100644
--- a/cmd/mstdn/cmd_stream.go
+++ b/cmd/mstdn/cmd_stream.go
@@ -13,6 +13,7 @@ import (
 )
 
 type SimpleJSON struct {
+	ID       int64  `json:"id"`
 	Username string `json:"username"`
 	Avatar   string `json:"avatar"`
 	Content  string `json:"content"`
@@ -41,6 +42,7 @@ func cmdStream(c *cli.Context) error {
 		} else if asSimpleJSON {
 			if t, ok := e.(*mastodon.UpdateEvent); ok {
 				json.NewEncoder(c.App.Writer).Encode(&SimpleJSON{
+					ID:       t.Status.ID,
 					Username: t.Status.Account.Username,
 					Avatar:   t.Status.Account.AvatarStatic,
 					Content:  textContent(t.Status.Content),
diff --git a/cmd/mstdn/cmd_toot.go b/cmd/mstdn/cmd_toot.go
index 9a82534..1889006 100644
--- a/cmd/mstdn/cmd_toot.go
+++ b/cmd/mstdn/cmd_toot.go
@@ -26,7 +26,8 @@ func cmdToot(c *cli.Context) error {
 	}
 	client := c.App.Metadata["client"].(*mastodon.Client)
 	_, err := client.PostStatus(context.Background(), &mastodon.Toot{
-		Status: toot,
+		Status:      toot,
+		InReplyToID: c.Int64("i"),
 	})
 	return err
 }
diff --git a/cmd/mstdn/main.go b/cmd/mstdn/main.go
index 7030370..a5656c8 100644
--- a/cmd/mstdn/main.go
+++ b/cmd/mstdn/main.go
@@ -174,6 +174,11 @@ func makeApp() *cli.App {
 					Usage: "post utf-8 string from a file(\"-\" means STDIN)",
 					Value: "",
 				},
+				cli.IntFlag{
+					Name:  "i",
+					Usage: "in-reply-to",
+					Value: 0,
+				},
 			},
 			Action: cmdToot,
 		},